Double-acting air pump



Nov. 20,1923

|. T. EASTMAN DOUBLE ACTING AIR PUMP Filed Jan. 5. 1922 2 Sheets-Sheet 1.i N Enf NN Nov. 20, 1923 v l. T. EAsrMAN DOUBLE ACTING AIR PUMP`-\Fi1\ee1rlan. 5, 1922 2 sheets-sheet 2 I/v VEN Taf?.

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y 4o throughoutv d' the Patented Nov. 26, 1923;

ravine fr. EASTMAN. or Conv, WYOMING, Assieme or ONE-HALF 'ro' noMAmorf-runNnA-roms; MINNESOTA.' .d

. -L MM5@ y @PArFEiNTI ori-reel'g-j n DOUBLELCTING faire PUMP. y

.Implication med January's, 1922. Serin no. 5:5?{1201 To @ZZ whom t mayconcern:

Be itl known that "I, IRVING T. EASTMAN;

acitizen of theUnitedStates, residing at Cody, inthecounty ofParkand4State of .5 lVyominO, have invented certain'new and useful Improvements'in Double-ActingAir Pumps; and I Clo-hereby declare the folien#l ingtobea full, clear, Vand' exact descriptionofth'e inventioin such as Willenable 'others skilled inthe-art to v#.vhfieh"'it appertains to makeyand use vthe "sam el.

This invention rela-teste man pimp aria v particularly-to a smallportableair pump` adapted toA bel clamped toI aboard 'or-other memberand foruse-fin'pumping-np automobile tires.

Y It is an object of this jinvention'to provide capacity and the airfrom the advancing` side' of thepiston inthe largerr cylinder beingdelivered tothe retreatingsidegrof the piston 4 in the smallercylinder.`

. It is still another object of theiinvention to 4utilize the pistonsand pistonvi'o'ds as yivell 3o asthe commoncrosshead Whiclractuates therods7 as the connecting'means for delivering the air from one cylinderto another, thus doing' away YWith-the necessity ofseparate conduits orpassages. Y

These and other objects of the invention Willpbe fully' setforthfin'thefollowing def scription VIn`ade'- in connection with the ac--jcompanying" drawings in VWhichf lilrefrefer-l Y enceeharact`e'r'sreferAtov the 'same -gparts'l different vieivsb` and-v `in' which,v ,l Fig.V lis a vieWin Sidefelevation of the pump 'showing the same clamped inposi? Fig. 2 is 'alcen'tral verticaljsection ofthe cylindersl andcresshead andf Fig. 8 is-a "vertical 'section 'italien on the ma?,sperrige Re erringto th legof which is adapted' tcontaet; With onesurfae fof a table {onboard-and *theother le Y Y Y .drawingsg thevdevice Y 50 comprisesfa Ushapedclampmeniberf1, one

4 thisfpassag'ek? -The-a n cate With chanibe vaarweg:einergeronan fand'V suitable handle '4. The upper .armbf 55 i the member l has'anupstanding-flug there` on and to 1 Which a'bifurcated arm ifis pivfoted'by a headed pivot pin G'heldin .position y bysuitablemeans, sueh asasplit''keypasslr` ing throughthe end thereof. The arm'f is" 60integrally. connected 'Withand disposed un-y der vthe cylinder head 5.'Thiscylinder headf 5 is in 'the'sha'pe of'anl oblong plate 'with fcircular ends,fone end bei-ngof'greater diam-i eter than `theother `andis` of substantially .65 the same outline :as the 'cylinder `head 7disf` posed -at the 'otheriend of ltrhefpump[and shown in Fig.` 3.The:cylinder heads "'and 7 have shallow Vcylindrical recesses formed`therein into Vwhich lare n fittedl the cylinder" 70 barrelsv 8k Aandy9. The headsf `and 7.. are, clampedy together onthe barrels 8 and 9 by;spaced headed .boltslO passing-4 throughlugfsin the headl 7`and'threaded into yCoriesp'ond'- inglugs on'thehead'. The Ahead 5isfprof` 75 vided With raisedboss'es 5b at vthe :centerso'fits circularportions which form stuffing"V` boxes rand are threaded tore'ceive theglands". l1 threaded thereinto. Th'ecylinder 8 is provided with apiston'lQ and the 'cy'li'ndei`l 9 180l is provided Withafpiston 13,Which pistons* are provided'with suitable pac'king'or pistonf rings toform a tight'fit with the cylinders.'

A piston rod 14: is secured to` the piston '12- by being soreivedthereinand a piston 41jod85 l5 is similarly secured to the piston 13,these if piston rods passing out'at the frontfend 'of the :cylindersthrough the stufling glands 1l.

suitable 'packing material being compressed? 'in the boxes 5b about'the' rodsby'thefsaid' 90 fi:

f ears 16a which leinbracela lever lZftojiw-liich theyffare pi-votally'Vsecured by a suitab'lydield pivot pin. Y The levcrw'ill be, latitsfvuppei1 en'd,"-provided with suitablefhandleg noti i showin and;-visf 'icurved' 'inwardlysomewhat" 100 at' its lofwerend andv-pivotedbetivee paced]-- their seats by coiled springs 19, the springsabutting said balls at one end and at their other ends abutting screwplugs threaded into said valve chambers from the faces of the pistonopposite the apertures above noted. It will thus be seen that theapertures communicating with chamber 12 are oppositely disposed and thevalves controlling the same are, likewise, oppositely disposed. Thepiston rod 141 has a passage extending axially therethrough which is inY communication with the passage '12a The crosshead 1G is also providedwith a passage 1 6"A with which the passage in piston rod 14communicates. A piston rod 15 is Aalso formed with an axial passagetherethorugh communicating with the passage 1G" in the crosshead at oneend and communicating at its other end with a chamber 13n formed in thepiston 13. The piston 13 is also pro-v vided vwith oppositely disposedapertures in the face thereof communicating with the passage 13fL andthese apertures are also controlled by spring pressed ballsy formingcheck valves, the springs being held in place by threaded plugs 20having central apertures therethrough. The crossheads 5 and 7 areprovided with slightly upstanding bosses opposite the lower ends of thecylinder 8 forming check valve chambers, the valves therein being alsool the springpressed ball type, the springs or' which are held in placeby apertured and threaded plugs vdisposed on the inside of the chamtbers. These valves control apertures in the top of said bossescommunicating with the atmosphere. The cylinder heads 5 and 7 are alsoprovided with chambers or passages 5 and 7c terminating at the inside ofsaid heads in threaded apertures and a suitably constructed conduit 21is connected with these threaded apertures and is provided with acentral discharge member 22 to which a flexible hose 23 may beconnected. The passages 5c and 7C communicate with valve chambers 5d and7Cl having apertures'communicating with the interior of the cylinder 9,these chambers being equipped with check valves in the form ofspring-pressed balls, the springs being held in place by a threaded plugscrewed into the outside of the cylinder head. Y

The operation of the pump is as follows:

The pistons 12 and 13 will be reciprocated i by oscillating movement ofthe handlel 17.

Assuming the pistons to be in the position shown in Fig. 2, when thesaine move to the right, the Vair will be compressed between the righthand side of the piston 12 and the right hand end of the cylinder 8.This compressed air will open the lower check valve shown in piston 12and the air will pass 'therethrough and through the passage throughpiston rod 14 through the passage 1Gb inthe crosshead, through thepassage through the tube or hose 23. The return of any of this air will,ot' course, be prevented by the check valve in chamber L piston moves tothe left on the return stroke, the air under pressure delivered at theleft hand side oi the piston 13 will be prevented from vagain passinginto the piston by the upper check valve of the piston and will open thevalve inchamber 7d passing through the passage 7C into the dischargeconduit 21 to be discharged' through the tube 23. This air will beprevented lfrom passing back into the. cylinder by the check valve inchamber 7 d. At the same time, the Apiston 12 will move to the left andthe air compressed between this piston and the lefthand end of thecylinder and will open the upper valve in the piston and passV throughthe piston rod 14; to crosshead 16 .and piston As th e rod 15, will bedelivered through vthe lower Y valve in the piston 13 and to the righthand or retreating side of the piston. Vith each stroke of the pump,therefore, the air compressed in the larger cylinder will be deliveredto the small cylinder and the air pre? viously delivered tothe smallercylinder will be discharged. at higher pressure. will be noted thatthere is .no inlet passage for air from the atmosphere to the'. highpressure cylinder 9. The air drawn into the pump will be taken at eachstroke through the inlet valves in the ends oi the cylinder 8.

From the above description it will be seen llO that applicant hasprovided an exceedingly y simple and useful pump. By passing the air`through the piston rods in the crosshead the structure is greatlysimplified and many parts eliminated. Thecylinders will voscillate aboutthe piston 6 as the pump is oscil-V lated and the tire or other memberto which the air is to be delivered will. soon be charged withair at ahigh pressure. The device is exceedingly compact, inexpensive to manufacture and can be quickly assembled.v The parts can also be readilytaken apart,'if for any reason this becomes necessary. The pump can bequickly and easily clamped upon the running boardA of an automobile,

on a table, or other suitable support. Y

It will, of course, be understood that various changes may be made inthe form, details and arrangement of the parts without departingv:trointhe scope of applicants invention, which, generally stated,consists in the matter shown and described and set l forth iii theappended claims.`

fwliat is claimed is: l. An air pump comprising high and low v .pressurecylinders, a piston in each cylinder,

l 2. The structure set forth in claim l, said low pressure cylinderhaving valve-equipped inlet openings at .each end and the high` Ypressure cylinder having valve-equipped discharge openings on each end.

3. An air pump comprising two parallel cylinders of `differentdiameters, a piston for each cylinder and a piston rod connected witheach piston, a cros'shead connected to said iodsl for simultaneouslymoving the same, -said pistons having oppositely facing valve-equippedopenings in the faces' thereof communicating with chambers therein, andthe chambers in said pistons in the respective pistons conmiunica'tingwith axial passages formed in the piston rods, said crosshead having achamber therethrough communicating with the passages in the piston rodswhereby when the pistons are reciprocated, air will be delivered fromthe advancing side of the larger piston to the retreating side of thesmaller piston.

4. The structure set forth in claim 3, said larger cylinder being closedexcept for valve-equipped openings at each end communicating with theatmosphere and said smaller cylinder being closed except forvalve-equipped discharge passages at each end thereof, and ya commondischarge conduit communicating with said passages.

5. AV portable hand-operated double-acting compound pump comprising twoparallel cylinders of different diameters, a piston in the largercylinder having a chamber therein and inwardly opening valves in eachface controlling communication with said chamber, a piston in thesmaller cylinder having al chamber therein, and outwardly opening valvescontrolling communication with the chamber therein, hollow pistonrodsconnected, respectively, to said pistons and 7'. A double-acting airpump having high communicating with the chambers the-rein, a crossheadconnected to" and adapted` to opeiate' said rods and pistons and having-a passage therethroughV communicating* with the passages through saidrods, air inlet means inthe larger cylinder and discharge means insaidsm'aller cylinder.-

Yas

6. A compounddouble-acting pump Yhaving high and low pressure cylinders,pistons having ,chambers therein in said cylinders and hollow pistonrods connectedy to said pistons and connnunicating with the chamberstherein, means having a passage therein connecting said rods andthepassages `therethrough, one of said pistons having an" inwardly openingvalvein each face'controlling communication with the chamber therein andthe other piston having an out-v wardly opening valve in each face,jsaidvalves controlling communication with' the chambers in said piston.

and low pressure cylinders relatively rigidly mounted for oscillatingmovement', apiston for each cylinder, a rod connected toeachpiston'having a longitudinal passage therethrough and projecting fromsaid cylinders at one end, a cross head connectingV said rods and havinga passage connecting the passages therein, Van oscillating leverpivvoted to said crosshead, and means in said pistons whereby air ispassed 4into' and .through said piston rods at each movementv of saidlever in either direction.

8. The structure set forth in'cla-im 6, the high pressure cylinderhaving outwardly opening valves in the end s thereof andthe low pressurecylinder having inwardly open-v ing valves in the ends thereof.

9.V A double-acting compound pump having high and lowpressurecylinders,` a piston in each cylinder having a chamber therein, eachpiston having check valves in both faces thereof controlling communicaftion with the chamber therein, the valves in one piston workingoppositely to the valves in the other, hollow piston rods connected tosaid pistons andV communicating vwith the chambersftherein andcommunicating with cach other, inlet means in the high pressure Ypressure cylinder. y ln testimony whereof I affix my signature'. Y lravine r. EASTMAN. lVitnes-ses: 4 s

J. FGUNsuL, F. F. MoGriiE.V

cvlinder' and discharge means in the p low` jVV y c f Y x10 .K

